|  | /* | 
|  | * Copyright (C) 2013 Apple Inc. All rights reserved. | 
|  | * | 
|  | * Redistribution and use in source and binary forms, with or without | 
|  | * modification, are permitted provided that the following conditions | 
|  | * are met: | 
|  | * 1. Redistributions of source code must retain the above copyright | 
|  | *    notice, this list of conditions and the following disclaimer. | 
|  | * 2. Redistributions in binary form must reproduce the above copyright | 
|  | *    notice, this list of conditions and the following disclaimer in the | 
|  | *    documentation and/or other materials provided with the distribution. | 
|  | * | 
|  | * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY | 
|  | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | 
|  | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | 
|  | * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR | 
|  | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | 
|  | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | 
|  | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | 
|  | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | 
|  | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | 
|  | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | 
|  | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | 
|  | */ | 
|  |  | 
|  | #pragma once | 
|  |  | 
|  | #if ENABLE(DFG_JIT) | 
|  |  | 
|  | namespace JSC { namespace DFG { | 
|  |  | 
|  | class BlockInsertionSet; | 
|  | class Graph; | 
|  | struct BasicBlock; | 
|  |  | 
|  | // Inserts dummy basic blocks before any loop headers that don't already have | 
|  | // a single non-loop predecessor. | 
|  |  | 
|  | bool performLoopPreHeaderCreation(Graph&); | 
|  |  | 
|  | // Creates a new basic block (a pre-header) that jumps to the given block. All | 
|  | // predecessors of the given block that aren't dominated by it are rerouted to | 
|  | // the pre-header. | 
|  | // | 
|  | // This function is used internally and it's used in a surgical fashion by | 
|  | // OSREntrypointCreationPhase. | 
|  | // | 
|  | // Note that executing this function requires having an intact dominators | 
|  | // analysis. You should run that analysis before doing damage to the CFG, even | 
|  | // if said damage is done before you call this. | 
|  | BasicBlock* createPreHeader(Graph&, BlockInsertionSet&, BasicBlock*); | 
|  |  | 
|  | } } // namespace JSC::DFG | 
|  |  | 
|  | #endif // ENABLE(DFG_JIT) |